1. Field of the Invention
The field of the invention is reciprocating pump polished rod packing seals.
2. Description of Related Art
Over 75 percent of artificially lifted producing oil wells are being produced with sucker rod pumping systems, with the sucker rod string terminating in a polished rod that extends from the well head to the atmosphere. Stuffing boxes, having packing seals about the polished rod, are utilized to prevent well fluids from escaping around the polished rod. Well fluids include corrosive hydrocarbons including salt water and natural gas.
Due to the wear and tear of the moving polished rod, the corrosiveness of some well fluids, and the pressure drop across the packing seal in the stuffing box, all stuffing boxes on sucker rod pumping systems will leak at some time, requiring the primary packing seals in conventional stuffing boxes to be replaced periodically.
What is needed is a more simplified, unique, flexible, pressure-regulating secondary packing arrangement in a unitized assembly, readily adapted to any manufacturer's stuffing box in the field or on new installations.